System Design And Experimental Study Of A Cable-driven Parallel Waist Rehabilitation Robot

Rehabilitation is one of today's hot issues in the field of international robot.It is related to many subjects and various complex problems.Medical research shows that task-oriented repetitive motion can improve muscle strength and coordination in patients with motor dysfunction.Nowadays the supply of traditional rehabilitation equipments cannot satisfy the need of more and more waist injury patients.A new cable-driven parallel waist rehabilitation robot is designed to help the patients recover movement ability of the waist.This paper has carried on the basic research to the waist rehabilitation robot system,including mechanism design,mechanics analysis,control system,experimental study.According to the motion characteristics of the waist,the robot,consisting of a cabledriven parallel platform,a lower extremity exoskeleton assisted mechanism and a fixing device of the upper limb,could perform some rehabilitation training of the lumbar 3-DOF rotation.Considering the coupling motion between the lower extremity and motion platform,the kinematic model is set up by introducing two set of coordinate system when the mechanical analysis of the robot is carried on.By using the Lagrange's equation,the dynamic model is established.The control algorithm of the waist rehabilitation robot is designed by using the two-layer controller.The low-level controller adopts the PID algorithm to control the position to ensure the accuracy of the robot.The high-level controller uses a fuzzy algorithm to adjust the parameters of the low-level controller according to the tension variation of the cables,which ensures the safe operation for the robot.